The present invention relates to an electronic printed chromatic elapsed time indicator device and to a method of indicating the elapse of a predetermined period of time. More specifically the present invention pertains to a solid state electrical device that measures and visually indicates the passage of a predetermined period of time and the various components of which can be formed by inexpensive printing methods and by lamination of the layers, which can be activated at point of use.
Many devices are known for measuring and displaying the elapse of predetermined periods of time such as hour glasses, mechanical stop watches, electronic stop watches, and liquid-diffusion time indicator devices. A need exists for an elapsed time measuring device that is electronic, solid state, reliable, easy to manufacture and inexpensive (less than 10 US cents). In particular there is a need for such devices in which the consumer activates the timing mechanism independent of the actual time and which will inform the consumer of the progress and elapse of a predetermined segment of time, for example, to signal users of glues and adhesives such as Solvite that requires a bonding process of at least 20 minutes before it takes effect. Another example is in food safety. Regulations require that during the preparation of cooked items uncooked ingredients must not remain unrefrigerated for more than four hours. A further example is in health care where various components in a catheter arrangement such as the manifold and bacteria filter need to be replaced within a specified period of time. Keeping track of such time segments can be confusing and can lead to errors and oversights by working staff. A device as described herein is therefore of value in notifying the consumer of the elapsed time from time of activation independent of actual time of a large variety of time dependable consumerables.